The methods have hardly changed at the GHM foundry of Sommevoire since the factory's inception in 1857. Though the site expanded the scope of its production to street furniture in the 1970s, the gestures remain the same. Before casting, the workers have to create a sand core suspended in the mold. It lets a 0.39 in (1 cm) space for the molten metal to pass when the part is hollow. The mold is coated with a layer of graphite to prevent adhesion.